I NEED HELP SETTING UP MY MULTI-ROUTER NETWORK.
I have a very large building with 4 wings. In the center of the building, I have one Ethernet Windows 2003 Server, a few Windows XP Ethernet computers and one MAIN TomatoUSB router. In each wing I have 10 Ethernet Windows XP desktops and a TomatoUSB router. ALL of those devices are connected through Ethernet switches.
CONFIG:
MAIN office router: DHCP, "access point"
WING routers: br0 WAN to LAN, "access point"
All routers have the same SSID (MUST STAY SAME)
There are some wireless devices, such as Windows 8 laptops that connect wirelessly.
The problem is that random Ethernet computers are having random problems connecting to server drives and require reboot to reconnect.
Another problem is that the Windows 8 laptops have sudden drops in internet connection ever couple hours.
I feel I have wrongly configured my network of TomatoUSB routers.
Based on the above info, WHAT WOULD BE THE BEST CONFIGURATION FOR MY ROUTERS?

NETWORK & CONNECTION PROBLEMS:

One problem is that ALL computers and laptops have trouble accessing the server drives, but brute-force clicking on network drive icons and accepting error messages regains access.
Another problem is that the Windows 8 laptops have random drops in internet connection ever couple of hours.
The last problem is that the Windows 8 laptops only sometimes WILL NOT show the network drives and network computers (except other wireless laptops), if your near a WING router.

I feel I have wrongly configured my network of TomatoUSB routers.

PLEASE NOTE: IT IS important to keep my SSIDs THE SAME on all routers.

Sounds like a hardware issue to me. That is how Buffalo radios behave when nearing end of life. What is the age of the routers ? Did you install them new and have had this problem since they were new ? Please accept my apologies in advance if you had already provided this information and I had misssed it due to the length of yer post.

Do any of the wireless devices cross the building and wireless connect to other routers? Do they have static IP addresses? Maybe you are getting conflicts between wireless devices and static IP devices on LAN? Could be running out of available IP addresses during lease period?

If it's not a hardware failure, maybe look at the settings for IP range and shorten the lease time.

Could the wireless signals be a bit too close together and sometimes cause confusion for the wireless devices as to which AP to connect with?

@GeeTek: They are brand new, straight out of the box. They are a Netgear WNR3500Lv2. The product was released in 2009 or 2010 I think, if that's what your asking. I only started having problems when I flashed over TomatoUSB. I have the same router at home with TomatoUSB, and it works just fine. But now we're talking about 5 different routers under the same SSID, 4 of which I want to act as wireless repeaters/range extenders.

@Robbo: Yes, people are walking around using Windows 8 laptops around the building. All wireless routers are connected through Ethernet. ALL devices, both wireless and Ethernet, have static IP addresses. The lease period is set to 60 minutes. I know they're not hardware failures, I bought 2 from one store and 3 from another. It's just networking issues. Would it make a difference if my wireless channel frequency was the same on all routers?

@ghoffman: Yes, all of my static IP's are outside the DHCP range. I do NOT have problems within the 60 minute DHCP lease. Problem usually happen randomly. Times vary widely. No, network servers errors DO NOT occur at the same time as internet problems.

@darkgreenmeme It always happens. It's not so much the internet that I'm primarily worried about, it's the Windows 2003 Server dropping connection. I have tried only using the main router, but that doesn't work. Windows 8 has been Microsoft's current OS since October 26, 2012. Haven't you seen the commercials? They released Windows 8 as stable in October of last year.

Maybe your thinking of Windows 8.1 (Codename: "Windows Blue")? That is presently in private beta and will be released on October 20 of this year.

I am primarily worried about not being able to connect to the server drives. I have a Windows 2003 Server. NO COMPUTER, whether connecting through Ethernet or WiFi, whether Windows XP or Windows 8 can connect to the server drives without losing connection within a 24 hour period.

The operating system is not the problem, it's my TomatoUSB configuration. I know that up front. I know that because I used the same router a few months ago with generic Netgear firmware and there weren't any problems.

Like I said, I tried isolating the problem to a specific router, such as shutting down the range extending dummy routers, but no luck. The main router is where I'm guessing something isn't configured properly.